• 1 min read GPT 5.3 Codex is now available on AI Gateway. • GPT 5.3 Codex brings together the coding strengths of GPT-5.2-Codex and the reasoning depth of GPT-5.2 in a single model that’s 25% faster and more token-efficient. • Built for long-running agentic work, the model handles research, tool use, and multi-step execution across the full software lifecycle, from debugging and deployment to product documents and data analysis. • Additionally, you can steer it mid-task without losing context. • For web development, it better understands underspecified prompts and defaults to more functional, production-ready output. • To use this model, set model to openai/gpt-5.3-codex in the AI SDK.

Article Summaries:

  • OpenAI has released GPT 5.3 Codex on its AI Gateway platform. The new model merges the coding capabilities of GPT‑5.2‑Codex with the reasoning depth of GPT‑5.2, delivering a 25 % faster, more token‑efficient solution. Designed for long‑running agentic tasks, it can research, use tools, and execute multi‑step workflows across the software lifecycle-from debugging and deployment to documentation and data analysis-while allowing mid‑task steering without losing context. For web development, it better interprets underspecified prompts and outputs production‑ready code. Developers can access the model via the AI Gateway SDK with the identifier openai/gpt‑5.3‑codex, and the platform offers unified API, usage tracking, and built‑in observability.

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